Aceves served as Boston's primary closer for much of the 2012 season and recorded a career-high 25 saves. He finished second among AL relievers with 84.0 innings and averaged a career-high 8.04 strikeouts per nine innings while going 2-10 with a 5.36 ERA in a team-leading 69 appearances. The 30-year-old leads the AL with 269.2 innings of relief work since 2009. Signed by Boston prior to the 2011 season, he owns a 26-13 record (.667) with a 3.56 ERA over 183 career major league outings (nine starts) between the New York Yankees (2008-10) and Red Sox (2011-12).

The 28-year-old Bailey was limited to 19 games for the Red Sox last year after opening the season on the 60-day disabled list recovering from right thumb surgery. He posted a 1-1 record with six saves, a 7.04 ERA, and 14 strikeouts with Boston and combined for a 1.42 ERA (1 ER/6.1 IP) with 10 strikeouts over six rehab appearances prior to his August 14 activation. Acquired from Oakland in December 2011, Bailey has 81 saves and a career 2.47 ERA to go along with an 8-11 record and 188 strikeouts over a four-year major league career with the A's (2009-11) and Red Sox (2012).

Bard, 27, appeared in 17 games for the Red Sox last season, including the first 10 starts of his career, and went 5-6 with a 6.22 ERA. In 209 big league appearances with the Red Sox over the last four seasons, he is 10-19 with five saves, a 3.65 ERA, and 251 strikeouts. He set new club single-season records for holds in both 2010 (1st in AL, 32) and 2011 (T-1st in AL, 34), and his 79 career holds rank fifth in the AL since the start of 2009. A first-round selection in the June 2006 draft, Bard also ranks among AL relief leaders in strikeouts (10th, 217) and opponent batting average (5th, .196) over the last four seasons.

Ellsbury, 29, hit .271 with 18 doubles, four home runs, 26 RBI, 43 runs and 14 stolen bases in 74 games with the Red Sox in 2012. He missed 79 games after suffering a right shoulder subluxation on April 13. He returned July 13 and played in 67 games.

Boston's first-round selection in the June 2005 draft, Ellsbury has a .297 career average with 124 doubles, 23 triples, 56 home runs, 261 RBI, 384 runs, and 189 stolen bases in 581 major league games, all with the Red Sox, from 2007-12. He earned All-Star, Silver Slugger, Rawlings Gold Glove and American League Comeback Player of the Year honors in 2011, finishing second in AL MVP voting that year.

A two-time All-Star closer, Hanrahan was acquired by the Red Sox in a six-player trade with Pittsburgh on December 26. The 31-year-old went 5-2 with a 2.72 ERA and 67 strikeouts over 59.2 innings in 63 games with the Pirates in 2012, finishing fifth in the NL with both 36 saves and a 90.0 percent save rate (40 chances). He held opponents to a .187 average last year, sixth-best among qualifying National League relievers. Hanrahan ranks fourth among NL relievers over the last two seasons with 76 saves and a 2.24 ERA (min. 100.0 IP). Selected by the Dodgers in the second round of the June 2000 draft, he has compiled a 22-17 record with 96 saves, a 3.74 ERA and 436 strikeouts in 353 games (11 starts) over his six-year major league career with the Nationals (2007-09) and Pirates (2009-12).

Miller, 27, went 3-2 with a 3.35 ERA and 51 strikeouts compared to 20 walks in 53 relief appearances with the Red Sox in 2012. He posted career-best marks in games, holds (13), ERA, WHIP (1.19) and opponent AVG (.194) en route to being named the Red Sox Fireman of the Year by the Boston BBWAA. Miller limited left-handed batters to a .149 average (13-for-87) last year, the second-lowest mark in the AL (min. 100 batters faced) and top by a Sox lefty since at least 1974, and stranded 39 of 46 inherited runners (84.8 percent) for the AL's fifth-best rate. Signed by the Red Sox as a minor league free agent in December 2010, Miller owns a 24-31 record with a 5.54 ERA and 339 strikeouts in 149 major league games (66 starts) over parts of seven seasons with the Tigers (2006-07), Marlins (2008-10) and Red Sox (2011-12). He was originally a first-round selection of Detroit in the June 2006 draft.

The 26-year-old Morales made 37 appearances last season, including a career-high nine starts, in his first full season in the Red Sox organization before missing the club's last 37 games due to injury. He totaled a 3-4 record with one save and a 3.77 ERA, including a 4.14 mark (21 ER/45.2 IP) as a starter and 3.23 (11 ER/30.2 IP) out of the bullpen. The left-hander struck out 76 batters, including an average of 9.26 strikeouts per 9.0 innings as a starter (47 K/45.2 IP), and limited left-handed hitters to a .184 clip (18-for-98) with just two extra-base hits all year. Acquired from the Rockies in May 2011, Morales is 11-16 with 11 saves, a 4.36 ERA, and 221 strikeouts in six major league seasons between the two clubs.

With today's agreements, left-handed pitcher Craig Breslow is the only remaining unsigned Red Sox player eligible for salary arbitration.